Reversing auxiliary locomotive



Jan. 7, 1930. J. A. McGREw REVEBSING AUXILIARY LocoMoTIvE mmm@ FiledJuly '14.; 1927 6 sheets-sheet 2 vvx e. i... m

Jam. 7, 1930. l J. l@n.ivlml-Ew 1,742,610

RENERSIM? UXILIARY LOCOMOTIVE Filed July.14. 1927 @Sheets-Sheet ,34

BYl

' INVENTOR .10h04 Marew.

ATTORNEY y Jan. 7, 1930.

.1.1 A. l'vlccavuw REVERSING AUXILIARY LOCOMOTlVE Filed July' 14. 1927 6Sheets-Sheet 4 INVENTOR Jan. 7, 1930. J. A. -McGREw REVBRSING AUXILIAR?Loco'MoTIvg Filed' Juxyr14. '1921 'a' Shengsheet .5

INVENToR ATTORNEY Patented dan. 7, 193@ iran STATES PAT-ENT" OFFCEV JOHNA. MCGREW, OF ALBANY, NEW YORK, ASSIGNOR TO IrJlI'ILllHElli:` STEELCOMPANY REVRSING AUXILIARY LOCOMOTIVE Application led July 14,

-My invention relates to power plants in general and particularly toauxiliary propulsion units which are adapted to railway vehicles for thepurpose of assisting the main propulsion unit to propel the same.

Heretofore, auxiliary 4propulsion units have been suggested fr railwayvehicles to supplement the tractive .power of themain propulsionnnit tostart and. accelerate the movement of trains. In such' former -con,-structions, the auxiliary propulsion unit is mounted on the vehicle injuxtaposition to a normally idle axle and a mechanism is provided tooperatively connect said unit to said axle when it isrequired to utilizethe loads on the wheels, associated with -said axle,. to provideadditional tractive power. Auxiliary propulsion units of theaforementioned type are disclosed in previous patents issued jointly tomyself and James T. Loreegthese patents heilig Letters Patent No.1,412,250, issued Apr. 11, 1922, which discloses an auxiliary propulsionunit, and Letters Patent No.-1,447,352, issued Mar. 6, 1923,`whichdiscloses a device `for causing entraining of an auxiliarypropulsionunit with a normally idle axle of a railway vehicle or the like. Thelatter device is actuated by motive fluid for said propulsion unit andoperateswhen the fluid is turned on to the latter, as fully explainedinsaid Letters Patent. In my copending application iiledjointly withRobert S. A. Dougherty, Serial No. 130,606, under date of Aug. 21, 1926,there is disclosedla mechanism which coacts with the action of thepropulsion unit to automatically cause the establishment of a drivingconnection between said unit and the normally idle axle. However, saidapplication and said Letters Patent provide only forthe transmission of4rotation from the propulsion unit to the axle in one direction, whereas,in the present application, I provide means whereby the rotation of thepropulsion unit may be reversed when desired.

In Letters Patent No. 1,447,853, issued to myself jointly with James T.Loree, under date of Mar. 6, 1923, I disclose a mechanism wherein meansare provided whereby therotation of the driven axle may be reversed1927. Serial No. 205,680.

requires additional lines and valve device for` controlling the supplyof fluid to such mechanisms, and, furthermore, it is extremely difficultto synchronize their operationwith the operation of the propulsion unit.

It is, therefore, one of the objects of my invention to entirely obviatethe use of such intermediary mechanisms and to provide means `adapted tooperatively connect the propulsion unit to the driven axle solely by theinitial turning over effort of said unit.

Another object of my invention is the provision of a novel and simplemeans adapted to coact with a railway vehicle propulsion unit toautomatically cause the latter to be operatively connected to a drivenaxle of such vehicle, during the initial operation ofsaid unit.

vide a driving connection between an auxiliary propulsion unit which isineffective when the propulsion unit is not in operation and isadaptedto be rendered edective by the. turningover of said unit ineither a forward.- or reverse direction.

Anotherpobject of my invention is to provide an arrangement, wherein anauxiliary propulsion unit supplements a mainjpropulsion unit for movinga vehicle or train of vehicles and including means for establishing adriving connection between the auxiliary propulsion unit and a normallyidle axle, and means adapted to automatically reverse the auxiliarypropulsion unit when the valves of thelatter are set for operating theauxiliary propulsion unit in a direction opposite to the operation ofthe main propulsion unit.

Another object of my invention is to prol Another object of my inventionisto prol 'l vide a mechanism for automatically reversing an auxiliarypropulsion unit, which is moved by a main propulsion unit in thedirection opposite to-'that in which the initial effort of the auxiliarypropulsion unit tends to move it, so that, upon reversal of the latterunit its power will supplement the motive power of main unit to increaseits tractive effort. A Other novel features willv be more fullyunderstood from the following description and claims taken with thedrawings in which;

Fig. 1 is a plan view of an auxiliary propulsion unit mounted on arailway vehicle truck and embodies one form of my invention;

Fig. 2 is a line II-.II in Fig. 1;

Fig. 3 is a. longitudinal section taken on line III-III in Fig. 1;

lIv-iv in Figi;

Fig. 4 is a longitudinal section taken on line Fig. 5 is aY transversesection taken on line V-V in Fig. 4; y

Fig. 6 is a transverse section taken on line Fig. 7 is a transversesection taken on line VII-VII in Fig. 1; A

Fi 8 is a transverse section taken on line VII VIII in Fig. 1;

Fig. 9 is a sideelevation` illustrating the position of the eccentriccrank relative to the crank shaft when the valve is set to operate theengine in the forward direction.

Fi 9 is a side elevation similar to Fig. 9, but s lowing theeccentriccrank -n reversed position relatively to the crank; Fig. 10 isa cross section taken :on line X-X in Fig. 1;. i

Fig. 11 is a ,partial cross section taken on line 'IV-IV in Fig. 1;

Fig. 11a is a fragmentary View showing the kev in its forward drivingposition;

Fig 11b is a fragmentary view showing the key in the reverse drivingposition; o

Fig. 12 is a side elevation of locomotive and tender having mountedthereon an auxiliary propulsion unit embodying one form of my invention.

Referring to the drawing: In Fig. 12, the locomotive is designated bythe numeral 10, and the tender by numeral 11. In the pre'- ferredembodiment of my invention the locomotive engine constitutes the primarypropulsion unit and the auxiliary propulsion unit 12 is mounted injuxtaposition with a.

normally disconnected load bearing axle 13. In the particular embodimentshown `in the drawing, the unit 12 is mounted in juxtaposition with anaxle of a tender truck, but;l however, it should be understood that anyload bearing axle of the train may be operatively connected to said unitin order tosupplement the tractive power of the primelongitudinalsection taken on mover, without departing from the spirit ofmy invention.

Referring now to Figs. 1 and 2, the frame 14 of the propulsion unit 12,is provided with spaced bearings 15 fitting the axle 13. The other endof the frame is preferably supported by a link 16 connected to the frame14 and extending upwardly to a supporting member, as illustrated anddescribedin a copending application of Richard J. McCarty, Jr.; SerialNo. 102,915, filed- Apr. 19, 1926. It will be understood that theforegoing description relates to a conventional mounting of a frame 14and does, not constitute an essential part of the present invention,.asvarious other ways of vmounting the frame may be adopted.

The auxiliary propulsion unit is 4preferably of a twin cylinder engineof thedouble acting type and upon the frame 14 there is .mounted a pairof steam receiving. cylinders 16', each of the cylinders being suppliedwith steam from the locomotive boiler through the conduit 17 andis'controlled by the engineer through the medium'of the throttle valve18. As the operating mechanism associated with each cylinder of the twincylinder engine is identical, I have confined the following descriptionto the operation of single set of,

mechanism in order to clarify the description. The cylinder 16 isprovided withv a reciprocating piston 19 connected to acrosshead 2Oslidably mounted on suitable bearings on the frame 14. Rodsv21. connectthe crosshead 20 to the crank pins ofthe crank shaft 23 which issuitably mounted in bearings attached to the frame 14. Intermediate thecylinders 16 Ais a steam chest 24 which is connected to the conduit 17and is provided with a steam port 25,and.`steam p'assages`26 and 27respectively. Steam is delivered to and exhausted from thecylinderthrough the latter passages. There is also associated with eachof the steam passages 26 and 27, a pair of exhaust passages 28 and 29respectively.

A piston valve 30 operates over the aforementioned port and passages andWhenthe valve is at its position shownin Fig. 2, steam is passing fromthe port 25 through the passage 26 to the cylinder. at the left-handside of the piston in Fig. 3 and steam is being exhausted from thecylinder at the righthand side of the piston through the passage 27 tothe exhaust passage 29. By referring lto Fig. 5. it will be lnoted thatthe bottom `walls of the exhaust passages 28 and 29 are at a. levelbelow the cylinders so that the liquid of the condensed steam does'liotcollect in the cylinders, but flows from the latter. by gravity. Thislatter construction eliminates the use of drain cocks which are usuallyprovided to drain the cylinder before the engine is operated underpower.

Thepiston valve 30 is operated from an eccentric crank 31 mounted on themain crank amaai@ pin of the crank shaft 23 and is disposed at theoutside of the connecting rod 21 (see Figs. 1 and 9). An eccentric rod32 transmits the motion of the crank 31 to the arm 33 of the rockershaft 34 which is journaled in suitable bearings on the frame 14 (seeFigs. V1 and 10), At the other end of the rocker shaft 34, is keyedanother arm 35 which is connected to the piston valve 30 through themedium of a valve stem 36.

The eccentric crank 31- is of novel construction. j Usually, theeccentric crank is fixedly mounted relatively to the main crank pin andis disposed angularly with respect thereto so that the crank pin at theextending end of the eccentriccrank moves in the path of a circleconcentric with the axis of the jour-- nal of the main crank shaft, thistype is exempliied by the well-known IValschaerts 'valve gear. Insteadof this latter type of construction, I provided an eccentric-crankcomprising a web portion 37 fixedly mounted on the main crank pin anddisposed in alignment therewith, so that, the journal member 38,projecting laterally at its extending end,

is disposed in axial alignment with the journal portion of the maincrank shaft 23.` The journal member 38 isy apertured, as at 39.Rotatably mountedon the journal member 38, isa'crank arm 40 having alaterally projecting lcrank pin 41 andto the latter is pivotally mountedthe eccentric rod 32. The crank arm is retained 'on the journal member38 by any suitable means, such asa bolt fastening means which passesthroughthe aperture 39. The relative rotation between -the member 38 andthe crank larm 40 is limited by the key 4 2, fixed to the crank arm 40,and projecting into a key slot 43 formed in the journal member 38. The.key 42 is narrower than the slot 43 to allow a limited angular movementbetween the'crank arm 40 and the crank shaft 23. It will be seen thatthe arm 40 is free to swing from the position, shown in Fig. 9,-to theposition shown in Fig. 9, while the main-crank shaft is maintainedstationary. Conversely, when the parts are positioned as in Fig. 9, themain crank shaft may rotate clockwise, through a limited angle withoutmovement Vto the arm 40. The amount of relative angular movement betweenthe main crank and the eccentric crank is limited by the engagement ofthe sides of the key 42 withv the 0pposed side faces of the key slot43.` The key and the key slot are so dimensioned that the 4crankshafthas a limited free angular movement with respect to the eccentric crankarm which y corresponds substantially to the amount of. relativemovement between the valve 30 and the piston 19, required t0 Ifeversethe engine. With valve gearing employed with engines of this type, it isusual, when it is required to reverse the engine to move-the valverelatively to the position of the piston at the point ofreversal,vbut.so far as I am aware, it has never been suggested to movethe piston relatively to the position of the valve at the timeofreversal.

Furthermore, it has heretofore been found mediary mechanism to changethe relative position of the piston and valve when the valve is moved tocause the reversal, whereas, I accomplish this reversal automatically,eliminatingv such intermediary mechanism, in the manner hereinafterdescribed. In order to counterbalance the inertia effects on the movingparts of the valve mechanism, I provide a counterbalancing device byextending the crank arm40 beyond the axis in the direction opposite tothe end having the crank pin 41 and increase the cross section thereofto secure the necessary weight. Fixed lto the central portion of thecrankshaft 23, is a toothed gear 44 disposed in alignment with and innieshed relation with a toothed gear 45 rotatably mounted on the axle 13and which is constrained by suitable means against axial movement onsaid axle. It will be noted in the preferred form shown in the drawingsthat the gears 44 and 45 are provided with herringbone gear teethin'meshed relation so that the resultant working forces between theteeth act in a medial plane which is transverse with respect to the axesof said gears and thus secures the constrainment of the gear 45 axiallysolely by virtue of the engagement between the teeth of said gears, andprovides a structure wherein the gear 45 is more or less self centeringwith respect to thel gear 44, and, furthermore, by such construction thenecessity of providing side beartatably mounted a friction plate 46which is f preferably formed from a plurality of segmental pieces boltedtogether, .as shown in Fig. 1 and rotatably mountedV on exterior bearingsurfaces formed on the bearings 15. While the plates 46 are adapted torotate relatively to said bearings, they preferably `are adapted to gripthe latter frictionally, so that, they are not a free running fitthereon, but, require a comparatively large amount of power to causerelative rotation, compared with the power which would be required torotate them, if, the contiguous bearing surfaces were the ordinaryrunning fits established in this class of work. The normal pressurebetween said bearing surfaces may be conveniently adjusted on account ofthe plate 46 being built up segmentalljgfor instance, shims or thenecessary to provide fairly complicated interm in saidv plates.Diametrically opposite the key member 48 and rotatably suspended on saidfriction plates is a counterbalance.51 which functions to balanceextraneous forces acting on keymember. 48 and the gear wheel structureduringr its rotation.

The key member 48 comprises a body portion 52 having a convex topsurface 53 and a pair of laterally, downwardly and oppositely projectingabutment portions 54 and 55 respectively. The key 48 is provided with aconcave bottom surface 56 which is concentric withand sufficiently clearof the surface of for the abutmentportions 54 and 55 respectively, whenthe key is rocked from its normal position, as hereinafter described.A

In operation, assuming that the relative position of the crank arm 40and the main crank is in the position shown in full lines in Fig. 9,then the relative positions of the piston 19 to the valve 30 is such,that, when steam is admitted to the steam chest, the main crankshaft'will rotate in the direction indicatedA by the arrow in Fig. 9..This rotates the gears 44 and 45 in the direction indicated by thearrows in Fig. 11, which is the direction tomove the vehicle forward.When the parts are relatedy asaforesaid, and assuming that the` valve'gear of the locomotive is set for the forward movement of the latter,the engineer opening the main throttle valve of the locomotiveadmitssteam to the main` propulsion unit to operate the locomotive inthe forward direction; the axle 13 turning freely within the gear 45. Inthe event that the engineer wishes to increase the tractive effort ofthe locomotive, he opens the throttle valve 18, preferably gradually,and admits `steam to the auxiliary propulsion unit, thereupon thecrankshaft is rotated and causes the rotation of the gear 45, by virtueof its meshed engagement with the gear 44 which is fixed tosaid shaft.During the initial angular movement of the gear 45, the friction plates46 tend to remain at rest, by virtue of their inertia and theaforementioned frictional grip on their respective bearings, and

this results in a relative angular movement 53 ofthe key.' Zhen the keyis thus tilted,

.the end dface of leg 54 engages one of the abutments 58 formed on theaxle 13, as shown in Fig. 11. The engagement of the key with the axle 13constitutes a driving connection between the gear 45 and the axle whenthe auxiliary propulsionunit is operated to supplement the tractiveeffort of the main propulsion unit in the forward direction.

The relative arrangement of the key'to the abutments of the axle 13, issuch, that while power is being transmitted from the auxiliary unit tothe axle, the key is maintained in contact solely by the resultant ofthe working forces set up between the contiguous surfaces of the axle,key and gear 45 respectively.

It will be noted, that due to the loose fit be tween the trunnion member49 and the apertures 50, said member is not subject to the drivingforces, but such forces are transmitted directly through the body of thekey which functions as a column structure between `gear 45 and theaxle13. When the about the radial line passing' thru the axis of the gear45, and the axle revolves freely in the gear 45. y

Assuming that the relative position of the piston 19 andthe valve 30remains as set in the aforementioned operation, and that'the valvegearing of the locomotive. is set to cause the reversal of the latter atstarting. When steam is admitted to the auxiliary unit, the latteroperates to move the vehicle in the opposite direction, that is, rotatethe gear 45 in the direction opposite to the direction of rotation ofthe axle 13. The initial rotation of the gear 4 5 causes the key to tiltand engage the axle, as described above. The power of the mainpropulsion unit being very much greater than that of the auxiliary unit,causes l gear 45 to rotate in opposition to the effort.

ofthe crank shaft. By virtue of its meshed relation with the gear 45,the crank shaft is forced to reverse its direction of rotation.

vOwing to the lost motion connection between the crank arm 40 and thecrank shaft 23, the piston is' caused to change its position with samedirection as the main ropulsion unit, and the gear 45 is immediate yaccelerated by the power of the auxiliary unit to rotate at a speedgreater than the speed of rotation of the axle'. During the initialacceleration of said gear, the k'ey rocks, by virtue of tbe lost motionbetween the friction plates 46 andthe gear 45, as formerly explained,from its last mentioned position to its position shown in Fig. 11b andthus effects'a driving connection between the gear 45 and the axlewhereby the auxiliary propulsion unit supplements the power of the mainpropulsion unit. So it is evident that regardless of the setting of thevalve Vof the auxiliary propulsion `unit, the latter may be operativelysecured to a normally idle axle by simpl admitting steam to said unit toobtain, a most immediately, synchronous operation with the mainpropulsion unit.

4It will be noted that gear 45 is materially larger than the gear 44, sothat when the aux` iliary unit is operatively connected to the axle 13,the latter rotates at a comparatively slow speed, compared to the speedof the crank shaft 23 and it will be further noted that relative angularmovement between the crank arm 40 and the crank shaft 23, when changingthe relative position of the piston and to the valve, as abovedescribed, is limited to less than half the angle of a completerevolution of the crank shaft. It will, thus appear, t at the automaticreversal of the auxiliary unit by the opposing effort oflthe main unitis effected during a fraction 0f a revolution of `the wheels mounted onthe axle 13.

It will be seen from the foregoing description that I have 'devised a.simple and novel arrangement for automatically entraining an auxiliarypropulsion unit with an axle normaly disconnected therefrom and effect-such entraimnent regardless of the direction of operation of said unitand eliminates the employment of any intermediary mechanism.Furthermore, I provide a novel combination with a main propulsion unitof an auxiliary propulsion unit, wherein the latter unit 1sautomatically reversed by the effort of the main unit without theemployment of intermediary reversing mechanism.

While I have shown my invention in but one form, it will be obvioustothose skilled in the art that it is not so limited, but is susceptibleof various other changes and modifications without departing from thespirit thereof, and I desire, therefore, that only such limitationsshall be placed thereupon as are imposed by the prior art or as arespecifically set forthiin the appended claims.

Having thus described my invention, what I claim as new and'desireto-secure by Letters Patent is:

l. In a power plant, the combination with a main power unit of anauxiliary power unit, a source of motive fluid supply, means to reversethe operation of the main power unit, and means depending upon theoperation of the latter unit to cause the reversal of the auxiliarypower unit and secure the synchronous operation of said units.

` said units, and means whereby said auxiliary power unit may bereversed in operation by the rotationzof said shaft.

3. In a power plant for propelling a vehi-l cle, the combination with amain propulsion .the axle.

4. In a power plant for propelling a vee hicle, the combination withamain propulsion unit, of an auxiliary propulsion unit, a normally idleaxle adapted to be rotated by the effort of the main propulsion'unit,and means coacting with the action of the axle to cause the reversal ofsaid auxiliary unit.

5. In an auxiliary locomotive 'propulsion unit, the combination of acylinder having ports, a piston within said cylinder, a valve forcontrolling said ports, a crank shaft, means operatively connecting thelatter to said piston, an eccentric member mounted on said crank shaft,a lost motion device connecting said member to said crank shaft, meansoperatively connecting said eccentric member to said valve, a drivinggear fixed to the latter, an axle, a driven gear rotatably mounted onsaid axle and in meshed relation to said driving gear, a carrier memberadapted to rotate about the axis of said axle, a key member adapted tooscillate on said carrier member, an abutment formed on said driven gearadapted to engage said key member, and an abutment formed on said axleadapted to be engaged by said key member during the rotation of saidcrank shaft.

6. In an auxiliary locomotive propulsion unit, the'combination of acylinder having ports, a piston -within said cylinder, a valve forcontrolling said ports, a crank shaft, means operatively connecting thelatter to said piston, an eccentric .member mounted on said crank shaft,a lost motion device connecting said member to said crank shaft, meansoperatively connecting said eccentric member to said valve, a drivinggear fixed to the latter, an axle, a driven gear rotatably mounted onsaid axle and in meshed relation to said driving vgear, a carrier memberadapted to rotate about the axis of said axle, a key member adapted tooscillate on said carrier member, an abutment formed on said driven gearadapted to engage said key member, and a pair of opposed abutmentsformed., on said axle, one of which is adapted to be engaged by said keymember during the rotation of the crank shaft in one direction, and theother of said pair of abutments being adapted to be engaged by said keyduring the rotation of the crank shaft in the opposite direction.

7. In an auxiliary locomotive propulsion unit, the combination of acylinder having ports, a piston within said cylinder, a valve forcontrolling said ports, a crank shaft,

` meansvoperatively connecting the latter to said piston, an eccentricmember mounted on said crank shaft, a lost motion device connectingsaid' member to said crank shaft, means operatively connecting saideccentric member to said valve, a driving gear fixed to the latter, anaxle, a driven geai` rotatably mounted on said axle and in ineshedrelation to said driving gear, a carrier ,member adapted to rotate aboutthe axis of said axle, a key memberadapted to oscillate on said carriermember, an abutment formed on said driven gear adapted to engage saidkey member, a series of abutnieiits formed on said axle adapted to beengaged by said key member during the rotation of said crank shaft inone direction, and a second series of abutments formed on said axleoppositely directed with respect to the first mentioned series andadapted to be engaged by said key member during the rotation of saidcrank shaft in a reverse direction.

8. Ina power plant for propelling a 'vehicle, the combination with amain propulsion unit of an auxiliary propulsion unit, an axle normallydisconnected from the latter unit, said auxiliary propulsion unitcomprising a cylinder having ports, a piston within said cylinder, avalve controlling said ports, acrank. shaft, a rod connecting said crankshaft to said piston, an eccentric device mounted onvsaid crankshaft andhaving a limited angular movement With respect thereto,instruinentalities connecting said eccentric device to said valve, adriving gear fixed to said crank shaft, a key member, adriven gearrotatably mounted on said axle and having a recess formed thereinreceptive of said key member, a carrier member'disposed at each side ofsaid driven'gear and rotatably mounted on bearings-coaxial with saidaxle, and an abutment formed onisaid driven gear adapted tobe engaged bysaid key member during the' rotation of said crank shaft, a`

beaiing-vengaging each of said carrier members and rotatably supportingsaid key niemberj-ii`ifdependently of said driven gear and said axle,and a pair of opposed abutments formed on said axle adapted to ,beengaged by said key member.

9. In a power plant for propelling a vehicle, the combination with amain propulsion unit of an auxiliary propulsion unit, an axle normallydisconnected from the latter unit, said auxiliary propulsion unitcomprising a cylinder having ports, a piston within y said cylinder, avalve controlling said ports,

a crank shaft, a rod connecting said crank shaft to said piston, aneccentric device mounted -on said crank shaft and having a limitedangular movement with respect thereto, instruinentalitics connectingsaid eccentric device to said valve, a driving gear fixed to said crankshaft, a key member, a driven gear rotatably mounted on said axle andhav- .10. In an engine construction, the combination with a drivingshaft, of a normally disconnected driven sliaft, a driving gear fixedtosaidqdriving sli-aft, a driven gear rotatably mounted on said drivenshaft in nieshedrelation to the first mentioned gear, a key 'membernormally disengaged from saidv driven shaft, means to support said keymember independentlyof said driven gear, an abutment formed on4 saiddrivenshaft, an abutment formed on said driven gear and means adapted torotate said driving shaft so that the driven gear moves angularly withrespect t0 said supporting means and causes said key member to beinterposed between said abutinents to establish a driving connectionbetween said shafts.

11.. `In an engine construction, in combina-l tion, a power cylinderhaving ports, a piston .Within the cylinder, a valve controlling saidports, a main crank, a rod connecting said piston to said main crank, aneccentric mem- Aber, means to connect said member to said valve, andalost motion connection between said eccentric member and said maincrank,wheieby the rotation of the latter in one direction secures thesynchronous operation'f the piston and the valve and whereby rotation;of the main crank in the oppositeidirect-ion causes a change in therelative position ,of the piston with respect to the va'lve.- v y A 12.In a power plant, the combination with a main propulsion unit of -anauxiliary vpropulsion unit, a source of motive fluid supply,

v osition fof the a driven shaft adapted to be rotated by either or bothof said units, and means coacting with said shaft to reverse saidauxiliary propulsion unit when said shaft is rotated througlrthe effortof the main propulsion in a direction to oppose the operation of theauxiliary propulsion unit.

13. In a railroad vehicle, in combination, a.

llO

unit, operating in opposition -to said main unit, a normally idle shaft,means to connectv said auxiliary unit to said shaft, and means a mainpower unit o f an auxiliary power j unit, operating in oppositionl tosaid main unit, a shaft normally disconnected from said auxiliary unit,means to connect said auxilf iaiy unit to said shaft, and means coactingwith the section of said shaft to cause said units to operate in unison.

16. Iii a power plant, the combination with a main power unit of anauxiliary power unit, operating in opposition to said main unit, ashaft, means to connect said auxiliary unit to said shaft, and meanscoacting with the action of said 4mainunit to cause said units tooperatein unison.

17. In combination with an engine of a shaft normally disconnected fromsaid engine and having an abutment formed thereon, and an entrainmentmechanism for connecting said shaft to said engine actuated bythe actionof the engine, including a driven gear rotatably mounted on said shaft,a bearing, a carrier member rotatably mounted on said bearing, means toadjust the running it ofn the carrier member with respect to itsbearing, and a key member rotatably mountedon said carrier memberintermediate said gear and said shaftv and adapted to engage saidabutment. y

.18. In an auxiliary locomotive, the combination of an axle, an en `nehavinga crank shaft and a frame, said rame having bearings freelymounted on said axle, a driving gear xed to said crank shaft, a drivengear rotatably mounted on said axle between said bearings and constantlyin' mesh with said driving gear and having a longitudinal re cess formedtherein, a carrier member disposed at each side of said driven gear androtatably mounted on a bearing portion formed on the exterior portion ofsaid bearings, means to adjust the running vit of one of said carriermembers with respect to its bearing, a key member extending through saidrecess and rotatably mounted on said carrier members, and an abutmentformed on said axle adapted to be engaged by said key member.

19. In an auxiliary locomotive, the combination of an axle, an enginehaving a crank shaft and a frame, said frame having bearings freelymounted on said axle, a driving gear fixed to said crank shaft, a drivengear, rotatably mounted on said axle between said bearings andconstantly in mesh with said driving lgear and having a longitudinalrecess formed therein, a carrier member disposed at each side of saiddriven gear and rotatably mounted on a bearing portion formedv on theexterior portion of said bearings, a key member extending through saidrecess androtatably mounted on said darrier members, and an abutmentformed on said xle adapted to be engaged by said key mem- 20.' In anauxiliary locomotive, the combination of an axle, an engine having acrank shaft and a frame, said frame having bearings freely mounted onsaid axle, a driving gear fixed to said crank shaft, a driven gearrotatablymounted on said axle between said bearings andiconstantly inmesh with said driving gear, and having a longitudinal recess formedtherein, a carrier member disposed'at each side ofsaid driven gear andirotatably mounted on a bearing portion formed on the exterior portion ofsaid bearings, a key member extending through said recess and rotatablymounted on said carrier members, and a. pair of oppositely directedabutments formed on said axle adapt'- .ed -to be engaged by said keymember.

. In an engine, the combination of a frame, anaxle, bearings engagingsaid axle for supportingsaid frame,- a cylinder on said frame andprovided with ports, a piston within said cylinder, a crankshaftsupported in bearings attached to said frame, a iod connecting saidpiston to said crank shaft, a valve controlling said ports, a journalmember fixed to said crank shaft and having a slot formed therein, aneccentric member mounted on said journal member, a key connected to saideccentric member projecting into said slot, said key being narrower thansaid slot so as to per-A mit a limited relative angular movement betweenthe eccentric member and the journal member, a driven gear having alongitudinal recess formed therein rotatably mounted about said axle anddisposed between said bearings, a driving gear fixed to said crank shaftand in meshed relation to said driven gear, a carrier member rotatablymounted on said bearings, a key extending thru said recess rotatablysupported on said carrier member, and an abutment formed on said axle'adapted to be engaged by said key memben.

22. In an engine, the combination of a frame, an axle, bearings engagingsaid axle for supporting said frame, a cylinder on said frame andprovided with ports, a piston within said cylinder, a crank shaftsupported in bearings attached .to said frame, a rod connecting saidpiston to said crank shaft, a

valve controlling Isaid ports, a journal member fixed to said crankshaft and having a slot formed therein, an eccentric member vmounted onsaid journal member, a key. connected to said eccentric memberprojecting into said slot, said key being narrower than said slot so asto permit a limited relative t angular movement between the eccentricmember and the, journal member, a drivenv A. 1an

gear having a longitudinal recess formed connected to said axle adaptedto be engaged by said key.

23. In an engine, the combination of a frame, an axle, bearings engagingsaid axle for supporting said frame, a cylinder on said frame andprovided'with ports, a piston withf in said cylinder, a crank shaftsupported in bearings attached to said frame, a rod connecting saidpiston to said crank shaft, a

valve controlling said ports, a journal meinber fixed to said crankshaft and having a slot formed therein, an eccentric member mount- .edon said journal member, a key connected to said eccentric memberprojecting intosaid y slot, said key. being narrower than said slotso asto permit a limited relative angular movement between the eccentricmember and the journal member, a driven gear having alongitudinal recessformed therein andA rotatably mounted about said axle and disposedbetween said bearings, a driving gear fixed to said crank shaft andinmesh with said driven gear',` a carrier member rotatably mounted on saidbearings, means to adjust the running fit of said carrier member withrespectto Said bearings, a-key extending through said recess rotatablysupported on said carrier member,-

yand a pair of oppositely disposed abutments connected to said axleadapted to be engaged by said key.

24. The method of assisting thetractive effort of a main propulsion unitof a railroad vehicle which consists, in admitting steam to an auxiliarypropulsion unit to effect, by the action of said auxiliary unit, anoperative driving connection between the auxiliary unit and an axle` ofsaid vehicle, and reversing the operation of the main propulsion unit toeffect, by the action of the latter unit, a reversal of the operation ofthe auxiliary propulsion unit.

25. In combination, a driving element, a driven element, a deviceestablishing a driving connection between said elements, said deviceincluding a key member engaging said driven element, a carrier memberfor supporting said key member, means to ac-tfuate said driving element,and friction means to retard the movement of said carrier member whensaid driving element is moved, whereby said key member is moved todisengage said driven element.

26. In combination, a driving'element, a driven element, a relativelyfixed member, and means to establish a driving Aconnection between saidelements; said means including a member movable with saiddrivingelement,

a drive member intermediate said elements normally disengaged fi'oin oneof the elements and mounted on said movable member,

and friction means engageable with said fixed member to retard saidmovable member and cause a lag between the latter member and the drivingelement, whereby said connection is effected.

In testimony whereof I hereunto affix my signature.

JOHN A. MCGREIV.

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